Inlet structure for turbomachine

ABSTRACT

The fluid turbomachine is provided with an inlet gas flow diffuser tube. The nose piece of the turbomachine is mounted within the inlet diffuser tube, in concentrically spaced relation thereto, by a pair of supporting bars extending transversely through the nose piece, the ends of the bars being affixed to the diffuser tube. The diffuser tube, in conjunction with the noise piece, provides an annular passage for the inflow of gas to the turbine wheel journaled inwardly of the nose piece. The nose piece is provided with integral nozzle blades positioned in the annular gas flow passage. A bar retaining means engages the nose piece supporting bars in their central area and is operable to deflect the bars and maintain the same in tight engagement with the nose piece.

United States Patent Miller et Oct. 2, 197 3 [21] Appl Inventors:

Assignee:

Filed:

INLET STRUCTURE FOR TURBOMACIIINE Arthur J. Miller, Irwin; Robert A.

Miller, Jeannette, both of Pa.

Carrier Corporation, Syracuse, NY.

June 6, 1972 [1.5. Cl 415/136, 415/209, 415/219 R Int. Cl. Fold 25/24, FOld 9/02 Field of Search 415/134, 136, 137,

References Cited UNITED STATES PATENTS Campbell et al 415/134 Primary ExaminerHenry F. Raduazo Attorney-J. Raymond Curtin [57] ABSTRACT The fluid turbomachine is provided with an inlet gas flow diffuser tube. The nose piece of the turbomachine is mounted within the inlet diffuser tube, in concentri cally spaced relation thereto, by a pair of supporting bars extending transversely through the nose piece, the ends of the bars being affixed to the diffuser tube. The diffuser tube, in conjunction with the noise piece, provides an annular passage for the inflow of gas to the turbine wheel journaled inwardly of the nose piece. The nose piece is provided with integral nozzle blades positioned in the annular gas flow passage A bar retaining means engages the nose piece supporting bars in their central area and is operable to deflect the bars and maintain the same in tight engagement with the nose piece.

5 Claims, 4 Drawing Figures llll PATENTEDUBT m 3762 833 SHEET 10F 2 PATENTEU GET 2 I973 SHEET 2 [1F 2 FIG. 4

FIG. 3

FIG. 2

INLET STRUCTURE FOR TURBOMACI'IINE BACKGROUND OF THE INVENTION In turbomachines of the turbocharger type as shown in U. S. Pat. No. 3,476,487, the nose piece and the nozzle blades are subjected to a pulsating gas flow in the form of exhaust gages from the internal combustion engine and such gases reach temperatures up to l,300 F. In the operation of such turbomachines, the components of the inlet structure are subjected to forces causing severe vibration of the parts, also the nose piece, nozzle blades and diffuser tube have induced therein varying temperature gradients of substantial magnitude, with the result the parts expand and contract unevenly. Accordingly, the difference in thermal growth between the components forming the inlet structure of the turbomachine have produced therein areas of fail ure in the parts.

Various arrangements have been resorted to to reduce the occurrence of fracture or failure in the nose piece, and the inlet nozzle blades. The disclosure in US. Pat. No. 3,476,487 previously mentioned, proposes an arrangement for the solution of the growth between the nose piece and the part in which it is mounted. Another solution is proposed in applicants co-pending application, Ser. No. 199,972, filed Nov. 18, l97l. While such proposals constitute improvements over the prior turbomachine art, they are not entirely satisfactory, particularly in the cost of manufacturing the turbomachine.

This invention is directed to a novel arrangement wherein the nose piece, including the nozzle blade structure, is restrained against vibration, but such parts are permitted to freely expand and contract with changes in temperature, without creating any objectionable stresses in the parts.

SUMMARY OF THE INVENTION The nose piece is mounted in the diffuser inlet tube, and maintained in concentrically spaced relation thereto, by a pair of support bars which extend through the nose piece and through the diffuser tube.

Bar retaining means is mounted within the nose piece, centrally thereof, and functions to stress the mounting bars by deflecting the bars in a direction axially of the nose piece. Preferably, the nozzle blades are formed integral with the nose piece.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical sectional view of the turbine portion of a turbocharger embodying our invention.

FIG. 2 is a view taken on line 2-2 of FIG. 1.

FIG. 3 is a fragmentary view illustrating a slight modiflcation in the supporting bar clamp block.

FIG. 4 is a fragmentary view taken on line 4-4 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT A turbine casing 10 is attached at one end to an intermediate casing 11, a portion of which is shown in FIG. 1. These casing sections are secured together as by screws 12. The opposite end wall of the casing 1 is formed with a circular shouldered opening in which is mounted the flange 13 of the diffuser inlet tube 14. The flange 13 is fixedly secured in the outer wall of the easing by bolts 15. An inlet manifold 16 is attached to the diffuser tube 14 as by screws 17. The casing 10 is formed with cored circumferentially extending passages 18 for the circulation of cooling water.

A shaft 20 isjournaled in the intermediate casing section 11. A turbine disc or wheel 21 is fixedly secured to the shaft 20 and is formed at its periphery with turbine blades 23. The turbine structure 21, 23, is positioned and dimensioned for rotation in the inner portion of the diffuser tube 14.

A nose piece consisting of an outer wall 25, merging at its periphery with an annular portion 27, is mounted in the diffuser tube 14, with the annular portion 27, arranged in concentrically spaced relation to the tube 14. The annular portion 27, in conjunction with the diffuser tube 14, forms an annular passage 30 in registration with turbine blades 23 for the impingement of fluid thereon to effect rotation of the turbine wheel 21 at high speed. This structural arrangement is in the form of a turbocharger. Hot exhaust gases from the internal combustion engine are supplied through the manifold 16 and the passage 30 to effect rotation of the turbine. The nose piece is provided with inlet nozzle blades 31, preferably formed integral therewith. The nozzle blades 31 are of the form shown in FIG. 4. The ends 32 are the inlet edges of the blades. It will be understood that an impeller, not shown, is attached to the opposite end of the shaft 20 and serves as the moving part of a centrifugal compressor for supplying air under pressure to the intake manifold of the engine.

This invention has to do with the turbomachine inlet structure including the nose piece and its mounting in the diffuser tube 14. The annular portion 27 of the nose piece is formed with apertures for the reception of a pair of nose piece supporting bars 35, 36. These bars extend transversely of the nose piece through the apertures formed therein, and across the annular fluid inlet passage 30. The end portions of the bars 35, 36 extend through aligned apertures formed in the diffuser tube 14. One of the supporting bars extends in angular relation to the other bar of the pair. Preferably the bars 35, 36 are disposed diametrically of the nose piece and the diffuser tube 14, with one bar extending in a direction perpendicular to the other bar (see FIG. 2).

Means is provided to restrain movement of the bars 35, 36 relative to the nose piece. The bar restraining means is in the form of a block 40 formed with apertures to receive the supporting bars 35, 36. The block is arranged centrally in the nose piece and means is provided to move the block in a direction axially of the nose piece to flex the bars 35, 36. In the construction shown in FIGS. 1 and 3, the block 40 is formed with a stud 43 extending through an aperture formed in the outer wall 25 of the nose piece. A nut 45 is threaded on the stud 43 and serves, when tightened, to draw the outer end of the block 40 against a shoulder area 47 in the outer wall 25 of the nose piece (FIG. 1).

In FIG. 3, the nut 45' is in the form of a sleeve nut formed with a radial flange portion 48 engaging the outer surface of the wall 25, the block 40 abutting against the inner end of the nut 45' when the same is tightened on the stud 43.

The bar receiving apertures in the block 40 are so arranged that when the nuts 45 or 45' are tightened to position the block 40 against the shoulder 47 or the inner end of the nut 45, the supporting bars 35, 36 are forcibly flexed in a direction axially of the nose piece, whereby the supporting bars are restrained from movement relative to the nose piece as will be apparent. The force of the engagement of the bars 35, 36 with the annular portion 27 of the nose piece is such as to maintain the bars in snug contact with the nose piece during operation of the turbomachine. That is these parts are restrained against vibration. However, the engagement between the supporting bars and the annular portion 27 is such, however, as to permit the growth between these parts because of expansion and contraction due to temperature changes.

Inasmuch as one of the supporting bars is disposed in angular relation to the other, there is no shifting of the nose piece relative to the inlet diffuser tube 14. Accordingly, when the nose piece is properly centered in the tube 14 and the nuts 45, 45 are tightened, the nose piece is maintained in proper concentric spaced relation to the tube 14.

The outer ends of the bars 35, 36 may be formed with apertures to receive lashing wires 50, which serve to prevent physical displacement of the bars 35, 36 in the event of fracture of the stud 43.

With our invention, the retained supporting bars inhibit wear at the apertures in the annular portion 27 of the nose piece, by the elimination of vibration induced in prior structures by the severe hot gas pulsations. Also, the locked cross bars 35, 36 alleviate the problem of the differential growth of the hotter nose piece with the respect to the cooler diffuser tube 14. The nose piece formed with the integral nozzle blades 31 eliminates the problem incident to the prior structures, wherein the nozzle blades were carried on a nozzle ring bolted to the inner end of the nose piece. Also, the nose piece structure does not include any parts which, due to failure or fracture, can come in contact with the turbine wheel 21 or the blades 23. On the other hand, it will be apparent that the components making up the structural arrangement of this invention are produced economically by simple machining operations.

While we have described a preferred embodiment of our invention, it is to be understood that the invention is not limited thereto, but may be otherwise embodied within the scope of the following claims.

We claim:

1. An elastic fluid turbomachine comprising a casing, a diffuser tube mounted in said casing, a nose piece positioned in said tube, said nose piece being formed with an outer wall, the periphery of said outer wall merging with an annular portion spaced concentrically within said tube and forming in conjunction therewith an annular fluid inlet passage, a bladed turbine wheel journaled in said casing and disposed inwardly of the nose piece with the wheel blades in registration with said inlet passage for the impingement of fluid flow thereon, said annular portion of said nose piece being formed with a circular series of integral nozzle blades disposed in said annular fluid inlet passage, said annular portion being formed with apertures, a pair of nose piece supporting bars extending transversely of said nose piece through said apertures and through aligned apertures in said diffuser tube, one of said bars extending in angular relation to the other bar of said pair, bar retaining means cooperable with said outer wall to forcibly flex the central portions of said bars in a direction axially of said nose piece.

2. A turbomachine structure as set forth in claim 1, wherein said annular portion being formed with apertures, a pair of nose piece supporting bars extending transversely of said nose piece through said apertures and through aligned apertures in said diffuser tube, one of said bars extending in angular relation to the other bar of said pair, bar retaining means cooperable with said outer wall to forcibly flex the central portions of said bars in a direction axially of said nose piece.

3. A turbomachine structure as set forth in claim 2, wherein said nose piece supporting bars are disposed diametrically of said nose piece.

4. A turbomachine structure as set forth in claim 2, wherein one of said nose piece supporting bars is disposed perpendicular to the other bar of said pair.

5. A turbomachine structure as set forth in claim 2, wherein said bar retaining means includes a block formed with apertures for the reception of said nose piece supporting bars and screw means operable to move said block toward said outer wall. 

1. An elastic fluid turbomachine comprising a casing, a diffuser tube mounted in said casing, a nose piece positioned in said tube, said nose piece being formed with an outer wall, the periphery of said outer wall merging with an annular portion spaced concentrically within said tube and forming in conjunction therewith an annular fluid inlet passage, a bladed turbine wheel journaled in said casing and disposed inwardly of the nose piece with the wheel blades in registration with said inlet passage for the impingement of fluid flow thereon, said annular portion of said nose piece being formed with a circular series of integral nozzle blades disposed in said annular fluid inlet passage, said annular portion being formed with apertures, a pair of nose piece supporting bars extending transversely of said nose piece through said apertures and through aligned apertures in said diffuser tube, one of said bars extending in angular relation to the other bar of said pair, bar retaining means cooperable with said outer wall to forcibly flex the central portions of said bars in a direction axially of said nose piece.
 2. A turbomachine structure as set forth in claim 1, wherein said annular portion being formed with apertures, a pair of nose piece supporting bars extending transversely of said nose piece through said apertures and through aligned apertures in said diffuser tube, one of said bars extending in angular relation to the other bar of said pair, bar retaining means cooperable with said outer wall to forcibly flex the central portions of said bars in a direction axially of said nose piece.
 3. A turbomachine structure as set forth in claim 2, wherein said nose piece supporting bars are disposed diametrically of said nose piece. Pg,8
 4. A turbomachine structure as set forth in claim 2, wherein one of said nose piece supporting bars is disposed perpendicular to the other bar of said pair.
 5. A turbomachine structure as set forth in claim 2, wherein said bar retaining means includes a block formed with apertures for the reception of said nose piece supporting bars and screw means operable to move said block toward said outer wall. 